A temporary loss of judgment and higher reasoning capability that one may experience immediately after consumption of KFC's double-down sandwich. Initial symptoms may include confusion, euphoria, and slurred speech. These are soon followed by loss of physical coordination and language ability (several patients have been observed to repeatedly utter variations of the phrase "hurr herp derp"). Patients may then enter a trance-like state for prolonged, variable amounts of time. A full recovery is typical within a few hours to a few days, although in some cases lasting brain damage has been reported.

In the hospital, it was discovered that what psychiatrists initially believed to be severe mental retardation was nothing more than a case of Double Down Syndrome after a late lunch.

When someone has twice the effects of down syndrome, (only reach 2 feet tall, and only live to the age of 20) , and they always double down. They are very poor with money, and are not very good at gambling.

"Man we kicked that midget's ass last night in the club at Hold 'em"
"Yea I know, he musta had double-down syndrome or somthin'; he never could go a hand without double-down'. "